Asteroid Radar Database
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1981 Midas (1973 EA)
Classification: APO [NEO, PHA]
H:15.22 mag, G:0.15

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History of Radar Detections
Year Month Transmitter Receiver Frequency Obs
1987 Sep Goldstone Goldstone 8560 [G]
1992 Mar Goldstone Goldstone 8560 [G]
2018 Mar Goldstone Goldstone 8560 [G]
2018 Mar Arecibo Arecibo 2380 [A]

Radar-Based Physical Properties
name symbol value units uncertainty reference notes
number of components N
morphological type
spectrum-based or image-based dimensions
maximum range extent Rmax km
minimum range extent Rmin km
maximum Doppler bandwidth Bmax Hz
minimum Doppler bandwidth Bmin Hz
effective diameter Deff km
quality code for size Q
shape-based dimensions
equivalent diameter Dequ km
extent along principal axis x Ex km
extent along principal axis y Ey km
extent along principal axis z Ez km
DEEVE extent along x Dx km
DEEVE extent along y Dy km
DEEVE extent along z Dz km
surface area A km2
volume V km3
spin period Pspin h
spin rate ω deg/day
YORP acceleration ω̇ deg/day2
spin axis ecliptic longitude λ deg
spin axis ecliptic latitude β deg
radar cross-section OC σOC km2
radar cross-section SC σSC km2
radar cross-section σT km2
projected area Aproj km2
radar albedo OC σ̂OC
radar albedo SC σ̂SC
radar albedo σ̂T
circular polarization ratio μC 0.65 0.13 2008Icar..198..294B Date: 1987T

Orbital Elements at Epoch 2022-01-21 00:00 TT from MPO660785 (heliocentric ecliptic J2000)
Element Value Units
e 0.6501354
a 1.776436 AU
i 39.82987 deg
om 356.85699 deg
w 267.82861 deg
ma 202.53298 deg
n 0.41627443 deg/d

Link to complete orbital information at Minor Planet Center

Earth Close-Approach Data (+/- 10 years)
date nominal distance RTT SNR/run at Arecibo
2013-09-30 13:54:00 0.28458 284.0 10.8
2018-03-21 21:21:00 0.08957 89.4 606.7
2032-09-14 14:57:00 0.08635 86.2 688.9

Link to complete Close-Approach Data on SBDB at JPL